Monolithic Cerium Oxide Nanoparticles Assembly for Wearable Electronics

Abstract

Cerium oxide nanoparticles (CeO2NPs) have shown par-excellent performance for applications like sensing, electrochemical catalysis, solar cells, chemical mechanical polishing/planarization, and catalytic converts. The nanoscale size combined with the available surface area that exposes highly active surface atoms/vacancies bring unique and highly desirable properties that opens up new possibilities in such application. However, large-scale processing of nanomaterials is challenging and necessitate scaling them up to macrostructure assemblies that can be easily handled without losing their original nanoscale size. In addition, assembling NPs into solid macrostructures would greatly impact applications that require handing gram-scale amounts of nanoparticles in solid-state processable form. Here, we describe a facile approach for synthesizing centimeter-sized porous monolithic CeO2 nanoparticles. This monolith is prepared though the hydrothermal treatment of the parent nanoparticles in solution to form a gel-like material, which turns into a crack-free solid monolith upon drying with a high surface area of 190 m2·g-1. As a proof of concept, we used CeNPs monolith/conductive polymer for detecting and quantifying solar radiation enabling this material useful for wearable electronics applications.